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Name __________________________
Tuesday, 11-29-16
Packet # 2 - 15
7th Science - ________
AIM: Define and describe the function of the digestive system. Explain
how the digestive and circulatory systems work together.
Quote of the Day: “Enthusiasm is the mother of effort, and without it
nothing great was ever achieved.” - Ralph Waldo Emerson
Do Now
Read/annotate the text before answering the questions that follow:
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The digestive system is a group of organs working together to convert food into energy
and basic nutrients to feed the entire body. The digestive system is made up of the
mouth, esophagus, stomach, small intestines, and large intestines. There are several other
important organs that help your body to digest food but do not have food pass through
them. These organs include the teeth, tongue, salivary glands, liver, gallbladder, and
pancreas. To achieve the goal of providing energy and nutrients to the body, six major
functions take place in the digestive system:
Ingestion: to take food into the body (to eat)
Secretion: releasing a substance for a specific purpose
Mixing and movement
Digestion: food is broken down physically by the teeth and chemically by enzymes; it is
then converted to a substance that can be absorbed into the body
Absorption: the body takes in nutrients
Excretion: discharge waste from the body
1. What is the purpose of the digestive system? (Use the text – what do these organs
do?)
__________________________________________________________________
__________________________________________________________________
2. During digestion, food passes through the alimentary canal, a long tube inside the
body. What is the alimentary canal made up of?
__________________________________________________________________
__________________________________________________________________
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PPT – Take notes in the spaces provided while discussing the PowerPoint
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The __________________________ system is a group of organs that work together
to break down food into energy and nutrients for the entire body
There are three main processes (“things”) that happen to our food when we eat it…
1. First, ___________________ (breakdown of food)
2. Second, _____________________ of Nutrients
3. Third, __________________________ (using the restroom)
There are two types of digestion:
1. ________________________: physically breaks down food
a. Chewing with your teeth
b. Food moving through your body
2. ________________________: chemical reactions occur to break down food
a. _____________________ in your mouth breaking down food
b. Hydrochloric acid in your _____________________ breaking down bolus
c. Enzymes in your small ____________________ that break down
materials
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FOOD’S JOURNEY THROUGH YOUR BODY – check off each body part at the
bottom of Page 2 as we discuss it.
There are _____ major events during digestion:
1) Chewing
2) Swallowing
3) Breakdown in _______________
4) Absorption in ____________________
5) Absorption in ____________________
6) Removal through the anus
1. ___________________________: food enters your mouth
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Your _____________ chew the food (mechanical digestion)
________________ also aids in breaking down the food (chemical
digestion)
Chewing turns the food into what we call a ______________
2. _______________________: bolus of food moves down your esophagus
towards the stomach
 ________________________: circular muscle motions that move in
waves to push a food bolus through the body
3. Breakdown in the _________________________
 The ______________ is mainly composed of hydrochloric acid that
decomposes your food
4. Absorption of nutrients in the ______________________________ (long,
skinny tube)
 Nutrients are absorbed by tiny finger-like structures called ____________
 Enzymes that cause the chemical digestion come from the
_______________
 The _________ that breaks down fatty foods come from the liver
Absorption of water in the __________________________________ (short, wide tube)
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Independent Work
Food’s Journey
Directions: Read and annotate the passage, answering the questions as you move
along
Food stores the energy your body needs to stay alive. But energy can only be
released from food by the mitochondria inside of your microscopic cells, and a Big Mac
is WAY TOO BIG to try to cram into your cells all at once! So your body must break it
down into much smaller pieces. Your digestive system breaks down the food you eat
into microscopic molecules that your body can use to make energy. Your digestive
system is like a long tube that runs through your body, from your mouth (where food
goes in) to your anus (where waste comes out), breaking down food along the way.
1. What does food store in your body? _________________________________
2. What is the function of the digestive system? __________________________
3. What is your digestive system like in your body? ________________________
________________________________________________________________
You put food into your mouth, of course . Your teeth chop up the food, and
your tongue helps by moving the food to the right places in between your teeth. Your
mouth also produces saliva (just a fancy word for your “spit”). Saliva makes your food
wet and squishy, and easier to chew. But saliva also has special chemicals in it that help
break down the food even more.
4. What is the first stop for the food in your digestive system? _________________
5. What is the function of your teeth? _____________________________________
6. Why does your mouth have saliva in it?
__________________________________________________________________
When the food has been chewed up into small enough chunks, you swallow it.
The chewed up food slides down a soft tube called the esophagus, which just carries the
food from your mouth to your stomach.
7. What is the function of the esophagus? __________________________________
__________________________________________________________________
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Your stomach is a muscular organ in your belly that “digests” (breaks down) the
food into even smaller pieces. Your stomach uses its muscles to tumble the food around
and grind it up. But it also uses stomach acid to break apart the food molecules even
further. Your stomach digests your food until it is like a thick milkshake
8. What is the function of your stomach? __________________________________
__________________________________________________________________
9. Your stomach digests food until it is like
_________________________________.
Then the digested food is ready to move into a long folded tube that is packed into
your belly below your stomach, called your small intestine. It may be skinny, but your
small intestine is not small at all (it’s more than 20 feet long!). Chemicals in your small
intestines break down your food even more.
10. What is the function of the small intestines? ______________________________
11. How long are your small intestines? ____________________________________
Now the food molecules (glucose) are small enough to pass through the walls of
your small intestine. Blood flows over the folds of your small intestine and picks up the
glucose. Your blood carries the glucose molecules to cells all around your body, from
your head to your toes, where they can be used for making the energy your body needs to
stay alive!
12. What happens when the food is broken down into small particles? ____________
__________________________________________________________________
Leftover food waste moves into your large intestine, which is a shorter, fatter tube. The
walls of your large intestine absorb water from the food waste. Solid waste is removed
from your body through a hole called the anus (time to go to the bathroom :o ). So your
digestive system breaks down food into microscopic nutrients that your body can use,
and gets rid of the waste parts from your food that your body does not use.
13. What happens to leftover waste? ______________________________________
14. What is the function of the large intestine?_______________________________
________________________________________________________
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WORD BANK
Bile
Capillary
Digestion
Enzyme
Large intestine
Liver
Mouth
Peristalsis
Saliva
Small intestine
Stomach
Teeth
Villi
Trachea
Pancreas
Esophagus
Directions: Match the words from the word bank with their correct definition
1. ____________________________________ A large, lobed organ that produces bile
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2. ____________________________________ Any of the tiny blood vessels
connecting that nutrients from the digestive system enters the blood
3. ____________________________________ A liquid produced by the liver that helps
digest fat
4. ____________________________________ Process by which the body changes
food so it can be used to supply energy
5. ____________________________________ the main part of the system of tubes by
which air passes to and from the lunges; also called the wind pipe
6. ____________________________________ a muscular tube which connects the
throat to the stomach
7. ____________________________________ a J-shaped, muscular sac that stores
food and helps digest it
8. ____________________________________ a fluid containing water, protein, salts,
and often a starch-splitting enzyme that is secreted into the mouth by the salivary
glands
9. ____________________________________ group of hard bony structures that are
usually located on the jaws of vertebrates and are used for seizing and chewing food
10. ________________________________ a short, wide tube in which water is absorbed
from undigested food
11. ________________________________ finger-like structures that cover the inner
wall of the small intestines
12. ________________________________ chemicals that break down food
13. ________________________________ the opening through which food passes into
the body
14. ________________________________ squeezing motion that pushes food through
the digestive system
15. ________________________________ a long, skinny tube in which food is
digested and nutrients absorbed
16. ________________________________ a gland that produces enzymes
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